The lines are anchored to the wall. There's no tension release on that. The gripper in the middle of the room unwinding some line won't prevent you, your child, or a pet from hanging themselves from the anchored end.

So it probably can't kill you with blunt force trauma but it could drop something toxic into your drink while you're in the other room. Which, you know, assumes some sort of hostile intent that a robot can't have on its own lol. So it can kill you but probably not accidentally.